This invention elates to self-propelled submersible suction cleaners, particularly swimming pool suction cleaners. The term "self-propelled" herein means that the suction cleaner is not manually propelled but incorporates means, such as an oscillator, operated by the flow of water through the suction head, to cause propulsion of the device.
Suction cleaners of the above kind usually incorporate a polymer skirt or base on which a housing for the propulsion mechanism rests. The skirt plays a part in the sweeping action of the device and also in its forward movement under the action of the propulsion mechanism. As an alternative to the use of a skirt, the housing or suction head may rest on bristles mounted on the head and projecting downwardly therefrom around the periphery of a mouth of the head. The bristles operate as a spring cushion to enhance the propulsion motion of the device but it is necessary to provide a skirt around the bristles in order to regulate the flow of water therethrough. Without the control of flow through the bristles the flow is spaced too far upwardly from the swept surface and the sweeping action is rendered inefficient.